linux-toradex.git/rust/kernel/scatterlist.rs, branch v6.19 Linux kernel for Apalis and Colibri modules rust: scatterlist: import ResourceSize from kernel::io 2025-11-13T09:17:24+00:00 Alice Ryhl aliceryhl@google.com 2025-11-12T09:48:34+00:00 ee2776e54b2666f99ef5e3ad0b60889e1500dada Now that ResourceSize has been moved to kernel::io, import it from the io module instead of the io::resource sub-module. It makes sense in this case since the dma_len isn't really related to the Resource type even though both are sizes of allocations in physical ram. Signed-off-by: Alice Ryhl <aliceryhl@google.com> Link: https://patch.msgid.link/20251112-resource-phys-typedefs-v2-3-538307384f82@google.com Signed-off-by: Danilo Krummrich <dakr@kernel.org> 
Now that ResourceSize has been moved to kernel::io, import it from the
io module instead of the io::resource sub-module. It makes sense in this
case since the dma_len isn't really related to the Resource type even
though both are sizes of allocations in physical ram.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251112-resource-phys-typedefs-v2-3-538307384f82@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
rust: scatterlist: Add abstraction for sg_table 2025-09-04T21:33:50+00:00 Danilo Krummrich dakr@kernel.org 2025-08-28T13:32:16+00:00 05aa6fb1c21d7fb9df735da24096d793223789d5 Add a safe Rust abstraction for the kernel's scatter-gather list facilities (`struct scatterlist` and `struct sg_table`). This commit introduces `SGTable<T>`, a wrapper that uses a generic parameter to provide compile-time guarantees about ownership and lifetime. The abstraction provides two primary states: - `SGTable<Owned<P>>`: Represents a table whose resources are fully managed by Rust. It takes ownership of a page provider `P`, allocates the underlying `struct sg_table`, maps it for DMA, and handles all cleanup automatically upon drop. The DMA mapping's lifetime is tied to the associated device using `Devres`, ensuring it is correctly unmapped before the device is unbound. - `SGTable<Borrowed>` (or just `SGTable`): A zero-cost representation of an externally managed `struct sg_table`. It is created from a raw pointer using `SGTable::from_raw()` and provides a lifetime-bound reference (`&'a SGTable`) for operations like iteration. The API exposes a safe iterator that yields `&SGEntry` references, allowing drivers to easily access the DMA address and length of each segment in the list. Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Tested-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Co-developed-by: Abdiel Janulgue <abdiel.janulgue@gmail.com> Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com> Link: https://lore.kernel.org/r/20250828133323.53311-4-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org> 
Add a safe Rust abstraction for the kernel's scatter-gather list
facilities (`struct scatterlist` and `struct sg_table`).

This commit introduces `SGTable<T>`, a wrapper that uses a generic
parameter to provide compile-time guarantees about ownership and lifetime.

The abstraction provides two primary states:
- `SGTable<Owned<P>>`: Represents a table whose resources are fully
  managed by Rust. It takes ownership of a page provider `P`, allocates
  the underlying `struct sg_table`, maps it for DMA, and handles all
  cleanup automatically upon drop. The DMA mapping's lifetime is tied to
  the associated device using `Devres`, ensuring it is correctly unmapped
  before the device is unbound.
- `SGTable<Borrowed>` (or just `SGTable`): A zero-cost representation of
  an externally managed `struct sg_table`. It is created from a raw
  pointer using `SGTable::from_raw()` and provides a lifetime-bound
  reference (`&'a SGTable`) for operations like iteration.

The API exposes a safe iterator that yields `&SGEntry` references,
allowing drivers to easily access the DMA address and length of each
segment in the list.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Co-developed-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
Link: https://lore.kernel.org/r/20250828133323.53311-4-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>